Single Antenna And Multi-antenna Conditions Qam Synchronization Technology

QAM (Quadrature Amplitude Modulation) is effective in frequentcy spectrum which is widely applied in modern communication systems. The great merit of MIMO (Murtipli-Input-Multiple-Output) is high usage of frequency spectrum and the MIMO technique gives high speed data transmit in multi-path fading channel. In recent years, MIMO has emerged as one of the most significant technical breakthroughs in wireless communications.In this essay, the author firstly researches the theory of QAM modulation and MIMO technique then constructs the synchronization system of SISO-QAM and MIMO-QAM. Beginning with the signal model of SISO-QAM and MIMO-QAM in burst mode, the author brings forward key techniques in system realization, including signal detection, reference parameter estimation, symbol timing recovery, phase tracking in SISO-QAM and training sequences, frame synchronization, carrier frequency offset estimation, symbol timing estimation.The dissertation concludes one portion of author's researches. It is organized as follows.Chapter I gives a brief introduction of QAM modulation and MIMO technique, compares MIMO-OFDM, MIMO-CPM, MIMO-QAM and gives the general work in author's research.Chapter II researches the theory of QAM modulation and MIMO technique, including performance of QAM modulation and MIMO systems, and key techniques of MIMO system realization such as space-time coding/decoding, frame synchronization, carrier frequency offset estimation, symbol timing estimation, channel estimation, single carrier-frequency domain equalization (SC-FDE), and design of training sequences and so on.Chapter III gives the synchronization algorithms of SISO-QAM in burst mode and gives the simulation results of synchronization system, including signal detection, reference parameter estimation, symbol timing recovery and phase tracking.The last chapter focuses on the synchronization algorithms of MIMO-QAM and gives the simulation results of synchronization system for performance evaluation, including frame synchronization, carrier frequency offset estimation and symbol timing estimation.Finally, according to the limitation of the system designed in simulation and the uncompleted part of the system such as space-time coding/decoding, channel estimation and SC-FDE, some ideas are discussed to construct the whole system and improve the performance for the future.